The invention relates to electronic fuel injection systems for internal combustion engines which employs an auxiliary air port to by-pass the throttle blade. More specifically, the invention relates to the art of varying the amount of auxiliary air which by-passes the throttle blade by changing the variable cross sectional opening of the auxiliary air port actuator in response to electrical pulses from a controller. The pulses are based on RPM changes due to changing loads on the engine. This air by-pass actuator is especially helpful at very low engine idle speeds where the throttle blade is nearly closed. The auxiliary air is supplied via the actuator in the by-pass port to control idle speed in response to engine loads, such as that due to air conditioning, automatic transmission, electrically heated backlights, etc.
An air by-pass valve representative of the prior art appears in U.S. Pat. No. 4,325,349.
One of the objects of the invention is to provide an auxiliary air by-pass actuator valve which is small in size.
Another object of the invention is to provide an auxiliary air by-pass actuator valve which can quickly respond to changing engine load signals.
The actuator valve described and claimed herein employs an air passage, which comprises a D-shaped orifice, a D-shaped notch and multiple orifices, gear reduction means and a motor assembly to drive the valve between the open and the closed postions, and a clutch assembly which helps to prevent the stalling of the motor if the valve reaches the full open or full closed position stops.
Accordingly, the present invention has among its further objects to provide an improved form of actuator valve employing a generally D-shaped valve and multifingered clutch.
The above and other objects and advantages of the invention will appear more fully from consideration of the following detailed description of the preferred embodiment of the invention made with reference to the accompanying drawings.